PENNSYLVANIA (PHILADELPHIA) STANDARD JOURNEYMAN PLUMBER 250_PA_PH CONTRACTOR EXAM - COMPLETE 350 QUESTIONS AND CORRECT ANSWERS What is the minimum pipe size for a water service

1. Q: What is the minimum pipe size for a water service line in
Philadelphia? ANSWER 3/4 inch diameter for residential properties.
2. Q: What is the maximum distance between cleanouts in a horizontal
drain line? ANSWER 100 feet maximum distance between cleanouts.
3. Q: What is the minimum slope required for a 4-inch horizontal drain
pipe? ANSWER 1/8 inch per foot (1% grade) minimum slope.
4. Q: What type of pipe joint is prohibited in Philadelphia plumbing code?
ANSWER Lead wool and oakum joints are prohibited in new construction.
5. Q: What is the minimum trap seal depth required? ANSWER 2 inches
minimum, 4 inches maximum trap seal depth.
6. Q: How many plumbing fixtures can be connected to a 3-inch soil stack?
ANSWER Up to 20 fixture units for residential applications.
7. Q: What is the minimum size for a main building drain? ANSWER 4
inches minimum diameter for main building drain.
8. Q: What is the required air gap for a dishwasher connection? ANSWER
1 inch minimum air gap above flood level rim.
9. Q: What is the maximum length allowed for a fixture trap arm?
ANSWER 2.5 times the diameter of the trap arm pipe.
10. Q: What pressure testing is required for water supply systems?
ANSWER 150 PSI for 15 minutes with no visible leakage.
11. Q: What is the minimum clearance required around a water heater?
ANSWER 6 inches on sides, 18 inches in front for service access.
12. Q: What size vent is required for a 3-inch soil stack? ANSWER
Minimum 2-inch diameter vent stack required.
13. Q: What is the maximum fixture unit load for a 2-inch trap? ANSWER
3 fixture units maximum for 2-inch trap.

,14. Q: What type of backflow prevention is required for commercial
buildings? ANSWER Reduced pressure zone (RPZ) backflow preventer.
15. Q: What is the minimum water pressure required at fixtures?
ANSWER 15 PSI minimum at highest fixture during peak demand.
16. Q: How often must grease interceptors be cleaned in restaurants?
ANSWER Every 90 days minimum, or when 25% full.
17. Q: What is the maximum temperature for hot water at lavatory
fixtures? ANSWER 120°F maximum temperature at point of use.
18. Q: What size expansion tank is required for a 50-gallon water heater?
ANSWER Minimum 2-gallon expansion tank capacity.
19. Q: What is the minimum burial depth for water service lines?
ANSWER 42 inches minimum depth below frost line.
20. Q: What type of pipe marking is required for potable water lines?
ANSWER Blue marking tape or paint indicating potable water.
21. Q: What is the maximum spacing for pipe hangers on horizontal runs?
ANSWER 10 feet maximum for 4-inch and larger pipes.
22. Q: What permit is required before beginning plumbing work?
ANSWER Plumbing permit from Philadelphia Department of Licenses &
Inspections.
23. Q: What is the minimum size for a washing machine drain? ANSWER
2-inch minimum diameter drain pipe.
24. Q: What backflow prevention is required for lawn sprinkler systems?
ANSWER Atmospheric vacuum breaker or pressure vacuum breaker.
25. Q: What is the maximum number of 90-degree elbows allowed in a
cleanout run? ANSWER Maximum of two 90-degree turns between
cleanouts.
26. Q: What insulation is required for hot water pipes? ANSWER R-3
minimum insulation on first 8 feet from water heater.
27. Q: What is the minimum size vent for a toilet? ANSWER 3-inch
minimum diameter vent for water closets.
28. Q: What separation is required between water and sewer lines?
ANSWER 10 feet horizontal separation, 18 inches vertical.

, 29. Q: What testing pressure is required for DWV systems? ANSWER 5
PSI air pressure test or 10-foot head water test.
30. Q: What is the maximum length for a bathroom group on 3-inch soil
stack? ANSWER 6 feet maximum developed length.
31. Q: What size gas line is required for a 75,000 BTU water heater?
ANSWER 3/4 inch minimum gas supply line.
32. Q: What earthquake restraint is required for water heaters? ANSWER
Seismic strapping at upper 1/3 and lower 1/3 of tank.
33. Q: What is the minimum size for a floor drain? ANSWER 2-inch
minimum diameter floor drain.
34. Q: What type of joints are required for ABS pipe? ANSWER Solvent
cement joints with primer application.
35. Q: What is the maximum horizontal run for a 1.5-inch trap arm?
ANSWER 3.5 feet maximum horizontal distance.
36. Q: What backwater valve is required in basement installations?
ANSWER Automatic backwater valve on building drain below grade.
37. Q: What is the minimum pipe size for a bathtub drain? ANSWER 1.5-
inch minimum diameter drain connection.
38. Q: What protection is required for pipes in walls? ANSWER Nail
plates when pipe is within 1.5 inches of stud face.
39. Q: What is the minimum size for a kitchen sink drain? ANSWER 1.5-
inch minimum diameter drain pipe.
40. Q: What pressure relief valve setting is required for water heaters?
ANSWER 150 PSI and 210°F temperature relief valve.
41. Q: What is the minimum trap size for a lavatory? ANSWER 1.25-inch
minimum P-trap for lavatories.
42. Q: What cleanout access is required for building drains? ANSWER
Cleanout within 5 feet of building exterior.
43. Q: What is the maximum fixture unit load for 1.5-inch drain?
ANSWER 3 fixture units maximum loading.
44. Q: What pipe material is prohibited for potable water systems?
ANSWER Lead pipes and lead-based solder prohibited.